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Internet Draft AAA Framework for Multicasting Feb. 2008
Internet Draft Hiroaki Satou, NTT
Intended Status: Hiroshi Ohta, NTT
Informational
Expires: August Christian Jacquenet, France Telecom
22, 2008
Tsunemasa Hayashi, NTT
Haixiang He, Nortel Networks
February 25, 2007
AAA Framework for Multicasting
<draft-ietf-mboned-multiaaa-framework-06.txt>
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Satou, Ohta, Jacquenet, Hayashi, He [Page 1]
Internet Draft AAA Framework for Multicasting Feb. 2008
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This Internet-Draft will expire on August 22, 2008.
Copyright Notice
Copyright (C) The IETF Trust (2008). This document
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Abstract
IP multicast-based services, such as TV broadcasting
or videoconferencing raise the issue of making sure
that potential customers are fully entitled to
access the corresponding contents. There is indeed a
need for service and content providers to identify
(if not authenticate, especially within the context
of enforcing electronic payment schemes) and to
invoice such customers in a reliable and efficient
manner. This memo describes the framework for
specifying the Authorization, Authentication and
Accounting (AAA) capabilities that could be
activated within the context of the deployment and
the operation of IP multicast-based services. This
framework addresses the requirements presented in
draft-ietf-mboned-maccnt-req-04.txt, "Requirements
for Accounting, Authentication and Authorization in
Well Managed IP Multicasting Services". The memo
provides a basic AAA enabled model as well as an
extended fully enabled model with resource and
admission control coordination.
Satou, Ohta, Jacquenet, Hayashi, He [Page 2]
Table of Contents
1. INTRODUCTION 4
1.1 PURPOSE AND BACKGROUND 4
2. DEFINITIONS AND ABBREVIATIONS 5
2.1 DEFINITIONS 5
2.2 ABBREVIATIONS 6
3. COMMON USE MODELS AND NETWORK ARCHITECTURE IMPLICATIONS 7
4. FRAMEWORK AND ROLES OF ENTITIES 8
4.1 "AAA FRAMEWORK IN MULTICAST-ENABLED ENVIRONMENTS 8
4.1.1 MULTIPLE CPS ARE CONNECTED TO MULTIPLE NSPS 9
4.1.2 MULTIPLE CPS ARE CONNECTED TO A SINGLE NSP 10
4.1.3 A SINGLE CP IS CONNECTED TO MULTIPLE NSPS 10
4.1.4 A SINGLE CP IS CONNECTED TO SINGLE NSP 10
4.2 USER ID 11
4.2.1 CP-ASSIGNED USER ID 11
4.2.2 NSP-ASSIGNED USER ID 11
4.3 ACCOUNTING 12
4.4 ACCESS CONTROL AND CP SELECTION BY NSP 13
4.5 ADMISSION CONTROL INFORMATION BY NSP 13
4.6 ACCESS CONTROL AND DISTINGUISHING OF USERS BY CP 14
Hayashi, He, Satou, Ohta [Page 3]
Internet Draft AAA Framework for Multicasting Feb. 2008
4.7 AAA PROXY IN NSP 14
5.1 BASIC CONNECTION MODEL 15
5.2 CONSTITUENT LOGICAL FUNCTIONAL COMPONENTS OF THE FULLY
ENABLED AAA FRAMEWORK 15
5.3 MODULARITY OF THE FRAMEWORK 19
6. IANA CONSIDERATIONS 19
7. SECURITY CONSIDERATIONS 19
8. CONCLUSION 19
1. Introduction
1.1 Purpose and Background
IP multicasting is designed to serve cases of group
communication schemes of any kind, such as 1-to-n (case of
TV broadcasting services for example) or n-to-p (case of
videoconferencing services, for example).
In these environments, IP multicast provides a better
resource optimization than using a unicast transmission
scheme, where data need to be replicated as many times as
there are receivers. Activation of IP multicast
capabilities in networks yields the establishment and the
maintenance of multicast distribution trees that are
receiver-initiated by nature: multicast-formatted data are
forwarded to receivers who explicitly request them.
IP multicast-based services, such as TV broadcasting or
videoconferencing raise the issue of making sure that
potential customers are fully entitled to access the
corresponding contents. There is indeed a need for service
and content providers to identify (if not authenticate,
especially within the context of enforcing electronic
payment schemes) and to invoice such customers in a
reliable and efficient manner. Solutions should consider a
wide range of possible content delivery applications:
content delivered over the multicast network may include
video, audio, images, games, software and information such
as financial data, etc.
Satou, Ohta, Jacquenet, Hayashi, He [Page 4]
Internet Draft AAA Framework for Multicasting Feb. 2008
This memo describes a framework for specifying the
Authorization, Authentication and Accounting (AAA)
capabilities that could be activated within the context of
the deployment and the operation of IP multicast-based
services. This memo also describes a framework to realize
high-quality multicast transport using a Multicast
Admission Control Function (MACF) with multicast
Authorization.
Specifically, this framework addresses the requirements
presented in draft-ietf-mboned-maccnt-req-05.txt,
"Requirements for Multicast AAA coordinated between Content
Provider(s) and Network Service Provider(s)" MACCNT-REQ-
draft describes the requirements in CDN services using IP
multicast[1]. The requirements are derived from:
- need for user tracking and billing capabilities
- need for network access control to satisfy the
requirements of the Network Service Provider (NSP) and/or
content access control to satisfy the requirements of the
Content Provider (CP)
- methods for sharing information between the network
service provider and content provider to make it possible
to fulfill the above two requirements.
Detailed requirements are presented in MACCNT-REQ-draft.
These requirements include mechanisms for recording end-
user requests and provider responses for content-delivery,
sharing user information (possibly anonymously depending on
the trust model) between content provider and network
service provider, and protecting resources through the
prevention of network and content access by unauthorized
users, as well as other AAA related requirements.
The purpose of this memo is to provide a generalized
framework for specifying multicast-inferred AAA
capabilities that can meet these requirements. This
framework is to provide a basis for future work of
investigating the applicability of existing AAA protocols
to provide these AAA capabilities in IP multicast specific
context and/or if deemed necessary, the refining or
defining of protocols to provide these capabilities.
2. Definitions and Abbreviations
2.1 Definitions
For the purpose of this memo the following definitions
apply:
Satou, Ohta, Jacquenet, Hayashi, He [Page 5]
Internet Draft AAA Framework for Multicasting Feb. 2008
Accounting: The set of capabilities that allow the
retrieval of a set of statistical data that can be defined
on a per customer and/or a per service basis, within the
context of the deployment of multicast-based services. Such
data are retrieved for billing purposes, and can be
retrieved on a regular basis or upon unsolicited requests.
Such data include (but are not necessarily limited to) the
volume of multicast-formatted data that have been forwarded
to the receiver over a given period of time, the volume of
multicast-formatted data that have been exchanged between a
receiver (or set of) and a given source over a given period
of time (e.g. the duration of a multicast session), etc.
Authentication: action for identifying a user as a genuine
one.
Authorization: The set of capabilities that need to be
activated to make sure a given requesting customer is (1)
what he claims to be (identification purposes), and (2) is
fully entitled to access a set of services (authentication
purposes).
Receiver: an end-host or end-client which receives content.
A receiver may be identified by a network ID such as MAC
address or IP address.
User: a human with a user account. A user may possibly use
multiple reception devices. Multiple users may use the
same reception device.
Note: The definition of a receiver (device) and a user
(human) should not be confused.
2.2 Abbreviations
For the purpose of this draft the following abbreviations
apply:
ACL: Access Control List
AN: Access Node
CDN: Content Delivery Network
CDS: Content Delivery Services
CP: Content Provider
CPE: Customer Premise Equipment
Satou, Ohta, Jacquenet, Hayashi, He [Page 6]
Internet Draft AAA Framework for Multicasting Feb. 2008
MACF: Multicast Admission Control Function
NSP: Network Service Provider
TS: Transport System
3. Common use models and network architecture implications
In some cases a single entity may design and be responsible
for a system that covers the various common high-level
requirements of a multicasting system such as 1) content
serving, 2) the infrastructure to multicast it, 3) network
and content access control mechanisms. In many cases
however the content provision and network provision roles
are divided between separate entities. The MACCNT-REQ-
draft provides more detail of the multiple versus single
entity CDS network models.
As such it should not be assumed that the entity
responsible for the multicasting structure and the entity
responsible for content serving are the same. Indeed
because the infrastructure for multicasting is expensive
and many content holders are not likely to be competent at
building and maintaining complicated infrastructures
necessary for multicasting, many content holders would
prefer to purchase transport and management services from a
network service provider and thus share the infrastructure
costs with other content holders.
Similarly network service providers in many cases do not
specialize in providing content and are unlikely to build
and maintain such a resource-intensive system without a
certain level of demand from content holders.
The use model of a single NSP providing multicasting
services to multiple CPs the following general requirements
from MACCNT-REQ-draft apply:
-Need for user tracking and billing capabilities
-Need for QoS control such as resource management and
admission control
-Need for conditional content access control
satisfactory to the requirements of the CP
-Methods for sharing information between the NSP and
CP to make the above two possible
When the NSP and CP are the same single entity the general
requirements are as follows.
Satou, Ohta, Jacquenet, Hayashi, He [Page 7]
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-Need for user tracking and user-billing capabilities
-Need for access control and/or content protection at
level the entity deems appropriate
4. Framework and Roles of Entities
4.1 "AAA Framework in Multicast-Enabled Environments
A general high-level framework can be represented as
follows.
+------------------------------+
| user |
| |
+------------------------------+
| Access ^ Response
| Request |
V |
+------------------------------+
| NSP |
| |
+------------------------------+
| Access ^ Response
| Request | (Success)
v |
+------------------------------+
| CP |
| |
+------------------------------+
Figure 1
For the sake of simplicity, the above diagram portrays a
case where there is a single NSP entity and a single CP
entity, but multiple CPs can be connected to a single NSP
(e.g. NSP may provide connections to multiple CPs to
provide a wide selection of content categories.) It is also
possible for a single CP to be connected to multiple NSP
networks (e.g. network selection). Furthermore it is
possible that the NSP and CP could be the same entity. A
NSP and CP authenticate and authorize each other when they
establish connectivity. Below the general case of multiple
NSPs with multiple CPs is explained. Then, the various
combinations of single and multiple CPs and NSPs are
described in relation to the general case.
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4.1.1 Multiple CPs are connected to multiple NSPs
The user subscribes to multiple NSPs and multiple CPs in
this usage case. The user selects a CP and a NSP when the
user requests content. The NSP may be automatically
selected by a user terminal: e.g. a fixed line NSP by a set
top box or a mobile NSP by a mobile phone. In some usage
cases it is possible that the NSP used by a certain user
will not always be the same. For example a user may have
contracted with more than one NSP: one for fixed line
access and another for mobile roaming access.
The content may be associated with (or managed by) a
specific CP. In this case, when the user selects content,
the CP is automatically selected.
The user should send an Access-Request to the selected NSP
with enough information not only for authentication by the
CP but also for CP selection and admission control by the
NSP.
When an NSP receives an Access-Request from a user, the NSP
selects the appropriate CP for the received Access-Request
and relays the content request. As the NSP is responsible
for managing its network resources, the NSP may perform
admission control.The NSP will allow access to the network
and contents conditional to both the CP's content
authorization result and the NSPs network availability.
That is, the NSP starts multicast flow only when it has
both 1) received an "accept" response from the CP and 2)
determined that the network resources (e.g. bandwidth) are
sufficient to serve the multicast channel. When neither of
these conditions are met, the NSP does not start the
requested multicast channel. When the NSP already knows
that network resources are insufficient or there is a
network failure, the NSP may choose to not relay the
Access-Request to the CP. The NSP is also responsible for
relaying the Response message from the CP to the user
whether the user is eligible to receive content (in
response to the corresponding Access-Request from the user
to the CP.) In cases that the NSP does not start
multicasting because of its own network issues (e.g. lack
of network resources or network failure), the NSP notifies
the user with a reason for rejecting the request.
A CP receives an Access-Request relayed by the NSP. The CP
authenticates the NSP's identity and makes an authorization
decision regarding the NSP's eligibility to provide users
access to its contents. The CP is responsible for
Authentication and Authorization of users' access to
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Internet Draft AAA Framework for Multicasting Feb. 2008
content that the CP manages. The CP hopes to collect
accounting information related to the access of their
content. The CP responds to the NSP regarding the relayed
Access-Request. When the CP cannot (e.g. error or
resource issues) or decides not (e.g. policy issues) to
deliver content, the CP is responsible for notifying the
NSP of the reason. It is up to the NSP how to relay or
translate the reasons for rejection to the user.
4.1.2 Multiple CPs are connected to a single NSP
The user subscribes to a single NSP which provides
multicasting of channels from multiple CPs in this usage
case. In this case the user does not select an NSP. The
user selects a CP when the user requests content. The
content may be associated with (or managed by) the specific
CP, so that when the user selects content, the CP is
automatically selected.
The user should send an Access-Request to the specific NSP
with enough information not only for authentication by the
CP but also for CP selection and admission control by the
NSP.
The role of the NSP is the same as that described in 4.1.1.
The role of a CP is the same as that described in 4.1.1.
4.1.3 A single CP is connected to multiple NSPs
A user subscribes to multiple NSPs but a single CP in this
usage case. A user selects the NSP when the user requests
content but the CP is fixed. The user should send an
Access-Request to the selected NSP with enough information
not only for authentication by the CP but also for
admission control by the NSP.
The role of the NSP is similar to the description in 4.1.1,
with the exception that when a NSP receives an Access-
Request from a user, NSP relays it to the CP without CP
selection.
The role of the CP is the same as that described in 4.1.1.
4.1.4 A single CP is connected to single NSP
In this case, a user subscribes to only one NSP and one CP.
The user does not select NSP and CP in this scenario. The
user should send an Access-Request to the NSP with enough
information not only for authentication by the CP but also
for admission control by the NSP.
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Internet Draft AAA Framework for Multicasting Feb. 2008
The role for the NSP is the same as 4.1.3
The role of the CP is the same as the description in 4.1.1.
The NSP and CP could be the same entity. In this case, the
roles of the NSP and CP may be combined.
4.2 User ID
Users may hold multiple user IDs: IDs which have been
separately assigned for each subscription they may have for
various NSPs and CPs. The NSPs and CPs manage the user IDs
for their respective domains. A CP identifies a user by a
user ID assigned by the CP itself. A NSP identifies a user
by a user ID assigned by the NSP itself. The user IDs are
only meaningful within the context of each domain. Users
may hold multiple user IDs which have been separately
assigned for each subscription they may have for various
NSPs and CPs.
4.2.1 CP-assigned user ID
CPs assign user IDs to their users. The user may have more
than one CP-assigned user ID per specific CP. A user sends
an Access-Request to a NSP, the CP-assigned user ID should
be indicated so that the CP can identify the user
requesting content access. A NSP should relay the CP-
assigned user ID from the user to the CP. A NSP should not
send a CP-assigned user ID to any CP except the one which
assigned it and should not relay it at all if there is no
appropriate CP that assigned the user ID.
4.2.2 NSP-assigned user ID
NSPs assign user IDs to their users. A user may have more
than one NSP-assigned user ID per a specific NSP. A user
sends an Access-Request to a NSP, the NSP-assigned user ID
may be indicated in the request so that the NSP can
identify the user. The NSP should not relay the NSP-
assigned user ID to the CP for security reasons. The NSP
may identify the multicast-access user by other methods
than the NSP-assigned userID, e.g. by the access port.
The actual mapping rules for NSP-assigned user IDs with CP-
user assigned IDs in account logs is a matter for the
providers and out of the scope of this framework.
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4.3 Accounting
There are some accounting issues specific to multicasting.
An (S,G) should be recorded as a channel identifier. The
last hop device, such as an IGMP or MLD router or an IGMP
or MLD proxy, notifies the NSP's AAA function of the (S,G)
channel identifier. The NSP should notify the CP of the
(S,G) information in the accounting report messages.
A NSP records an accounting start corresponding to only the
first Join for a specific user-access session. A NSP should
not treat a "Join" response to a Query as the accounting
start.
A NSP records an accounting stop triggered by any of the
following: 1) a user requested Leave, 2) a timeout of a
multicast state or 3) a re-authentication failure. A NSP
may also record an accounting stop due to network
availability reasons such as failure. The NSP logs the
reason for each accounting stop.
Intermittent logs between the join and leave would allow
for finer diagnostics and therefore could serve useful in
billing discrepancies, and provide for a better estimation
of the time-span that content was multicasted, in the event
that users disconnect without sending leave messages.
There are two levels of accounting report messaging.
Messages in Accounting level 1 include a channel identifier,
a user identifier, and the accounting start and stop time
information. Accounting level 2 includes all information of
Level 1, plus traffic volume information.
QoS class is an optional item for each accounting level.
Whether to send, and at what interval to send intermittent
log information is optional for both levels. CP and NSPs
may also agree to include additional option information in
accounting messages of either level.
The level of account report messaging between the NSP and
CP may be either configured statically or can be
dynamically requested by the CP in its response to the
Access-Request relayed by the NSP to the CP. The
determination of the actual level of report messaging is
configured by the NSP at the NAS.
In case of very fast channel changes, the amount of items
logged by the NSP could become high. In order to reduce
the number of report messages sent to the CP, the NSP can
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Internet Draft AAA Framework for Multicasting Feb. 2008
consolidate multiple sets of accounting information inside
a single accounting report message. [4]
4.4 Access Control and CP selection by NSP
When a NSP receives an access request from a user, the NSP
determines to which CP the request is to be directed. The
NSP may select a CP based on CP-assigned userID with CP
domain name or channel identifier (S,G). The user should
include in the request sufficient information for CP
selection.
4.5 Admission Control Information by NSP
After authorizing a user request, the NSP may have further
conditions for determining its admission control decision.
The NSP receives traffic parameters (such as QoS class,
required bandwidth, burst-size, etc.) of a multicast
channel. Such parameters serve as information to be
considered in the admission control decision. The traffic
parameters can be communicated as follows:
- A CP may notify a mapping between the channel
identifier (S,G) and traffic parameters in the Response
message when the CP authorizes an access request. Such
parameters may include required bandwidth, burst-size, QoS
class downgrade policy, etc.
- A user may indicate in the Request willingness to
accept QoS class downgrade to best-effort streaming.
- The NSP may maintain a mapping between channel
identifier (S,G) and traffic parameters in advance, for
example pre-configured by agreement between the CP and NSP
on a per channel basis.
The ultimate admission decision is made by the NSP based on
required traffic parameters of the requested, and available
resources. In a case that it cannot guarantee the required
network resources for the requested channel, streaming the
requested channel as best-effort traffic is optional.
The user may indicate in his/her Access Request whether
he/she will accept best-effort grade streaming if
guaranteed class is not available. The CP's preference for
accepting downgrading to best-effort streaming may be
either configured statically or can be dynamically
requested by the CP in its response to the Access-Request
relayed by the NSP to the CP. In the case that it cannot
offered a guaranteed QoS stream, the NSP may decide to
either to decline admission or to stream the requested
Satou, Ohta, Jacquenet, Hayashi, He [Page 13]
Internet Draft AAA Framework for Multicasting Feb. 2008
channel as best-effort traffic. The NSP should not stream
best-effort traffic if either the user or CP has indicated
against best-effort provision.
A NSP's admission control may manage integrated network
resources for unicast usage, such as VoIP or unicast
streaming, and multicast usage. Alternatively, it may
manage network resources separately for unicast and
multicast usage. In either ease, AAA and admission control
framework for multicast usage is independent of unicast
admission control.
Such QoS measurement and policy mechanisms themselves
depend on NSP policies and are out of the scope of this
memo.
4.6 Access Control and Distinguishing of Users by CP
The user ID and authentication information are forwarded
transparently by the NSP so that the CP can distinguish the
user, as well as authenticate and authorize the request.
4.7 AAA proxy in NSP
A NSP may act as AAA proxy of a CP based upon an agreement
between the NSP and the CP. The AAA proxy would store
information about permissions of a specific user to receive
multicast data from specified channel(s) up to specified
expiration date(s) and time(s).
If such proxying is implemented, the NSP may receive
authorization conditions from a CP in advance and
statically hold them, or a CP may send them dynamically in
the Response message. In either case, the user has
permission to receive multicast channel and therefore the
NSP starts the multicasting without querying the CP.
The CP may send unsolicited requests to the NSP to refresh
or change the permissions for a user for specific
channel(s).
When a user is receiving multicast content and the
permission is about to expire, the NSP may send a
notification to the user client that his session is about
to expire, and that he will need to reauthenticate. In such
a case, the user will have to send the Access-Request. In
the case that the user still has permission to the content,
they should be able to continue to receive the content
without interruption.
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When re-authentication fails, the NSP should stop the
multicast channel and record accounting stop.
5. Network Connection Model and Functional Components
Section 3.1 introduces the high-level AAA framework for
multicasting. This section provides more detail on the
network connection model and constituent functional
components.
5.1 Basic Connection Model
In the simple case represented in Figure 1 the NSP is the
sole entity providing network resources including network
access to the User. First a user that requests content
sends an Access request to an NSP which then forwards it on
to the appropriate CP for Authentication and Authorization
purposes. The CP responds with either "success" or
"failure". If "success", the NSP may forward a success
response and stream multicast data to the user.
In this model the user selects the NSP to which to send its
content request. Based on this request the NSP selects an
appropriate CP to which it forwards the request. The CP
responds to the NSP's request: it may not respond to
another NSP in regards to the request.
In this model, as described in section 3.1, the
relationship between NSP and CP can be 1:1, 1:N or M:N.
Users may connect to multiple networks, and networks have
multiple users.
5.2 Constituent Logical Functional Components of the fully
enabled AAA Framework
Requirements for "fully AAA and QoS enabled" IP
multicasting networks were defined in MACCNT-REQ-draft. To
allow for levels of enablement, this memo defines two
models within the framework: "AAA enabled" multicasting and
"Fully enabled AAA" multicasting which means "AAA enabled"
with added admission control functions.
Section 3.1 introduces the high-level AAA framework for
multicasting. Below is a diagram of a AAA enabled
multicasting network with AAA, including the logical
components within the various entities.
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AAA enabled framework (basic model)
+-------------------------------+
| user |
|+- - - - - - - - - - - - - - -+|
|| CPE ||
|| ||
|+- - - - - | - - - - - - - - -+|
+-----------|-------------------+
|
-------|------ IFa
|
+-----------|-------------------+
| NSP | |
|+- - - - - |- -_+ |
||TS | | |
| +------|-+ |
|| | AN | | |
| | |---------+ |
|| +------|-+ | | |
| | IFb | |
|| +------|-+ | | +---------+|
| | |----|-|mAAA ||
|| | NAS | | | |(MACF *) || * optional
| +--------+ +---------+|
||+- - - - - - - + | |
+-----------------------|--------+
|
-------|------ IFc
|
+-----------------------|-------+
| CP +---------+ |
| | CP-AAA | |
| +---------+ |
+-------------------------------+
Figure 2
The user entity includes the CPE (Customer Premise
Equipment) which includes the user host(s) and optionally a
multicast proxy (not shown in the Figure 2.)
The NSP (Network Service Provider) in the basic model
includes the transport system and a logical element for
multicast AAA functionality. The transport system is
comprised of the access node and NAS (network access
server.) An AN may be connected directory to mAAA or a NAS
relays AAA information between an AN and a mAAA
Descriptions of AN and its interfaces are out of scope for
this memo. The multicast AAA function may be provided by a
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Internet Draft AAA Framework for Multicasting Feb. 2008
multicast AAA server (mAAA) which may include the function
by which the access policy is downloaded to the NAS
(conditional access policy control function.) The interface
between mAAA and the NAS is labeled IFb in Figure 2. Over
IFb the NAS makes an access request to the NSP-mAAA and the
mAAA replies. The mAAA may push conditional access policy
to the NAS.
The content provider may have its own AAA server which has
the authority over access policy for its contents.
The interface between the user and the NSP is labeled IFa
in Figure 2. Over IFa the user makes a multicasting
request to the NSP. The NSP may in reply send multicast
traffic depending on the NSP and CP's policy decisions.
The interface between the NSP and CP is labeled IFc. Over
IFc the NSP requests to the CP-AAA for access to contents
and the CP replies. CP may also send conditional access
policy over this interface for AAA-proxying.
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Internet Draft AAA Framework for Multicasting Feb. 2008
Fully enabled framework
+-------------------------------+
| user |
|+- - - - - - - - - - - - - - -+|
|| CPE ||
|| ||
|+- - - - - | - - - - - - - - -+|
+-----------|-------------------+
|
-------|------ IFa
|
+-----------|-----------------------+
|+- - - - - |- - _+ + - - - - - + |
||TS | | | | | |
| +------|-+ | +--------+ |
|| | AN | | | | | MACF || |
| | | | | | |
|| +------|-+ | | | +---|----+| |
| | | | | |
| | | | IFd----- | |
| | | IFb | | |
|| +------|---+ | | | +---|----+| |
| | |---|---| mAAA | |
|| | NAS | | | | |(MACF *)|| | * optional
| +----------+ | +--------+ |
||+- - - - - - - -+ - - |- - - - -+ |
+-----------------------|-----------+
|
-------|------ IFc
|
+-----------------------|-------+
| CP +---------+ |
| | CP-AAA | |
| +---------+ |
+-------------------------------+
Figure 3
In the fully enabled model the NSP also includes a
component that provides network resource management (e.g.
QoS management), as described in section 3.4, "Network
Resource Management by NSP". In the fully enabled model
(Figure 3) resource management and admission control is
provided by MACF (multicast admission control function.)
This means that Before replying to the user's multicast
request the mAAA queries the MACF for a network resource
access decision over the interface IFd. The MACF is
responsible for allocating network resources for multicast
traffic. So that MACF has the necessary network resource
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availability information, NAS notifies MACF via mAAA of the
stopping of multicast traffic.
5.3 Modularity of the framework
In the interest of flexibility, this framework is modular
so that it is possible that partially enabled versions of
the models are supported. A AAA-enabled version provides
AAA functionality without Network Resource management. A
Network-Resource-Management-enabled (QoS-enabled) version
provides Network Resource management without AAA
functionality. Similarly, the possibility of one or more
layers of transit provision between an NSP and CP is in the
interest of modularity and extendibility.
6. IANA considerations
This memo does not raise any IANA consideration issues.
7. Security considerations
Refer to section 3.3. Also the user information related to
authentication with the CP must be protected in some way.
Otherwise, this memo does not raise any new security issues
which are not already addressed by the original protocols.
Enhancement of multicast access control capabilities should
enhance security performance.
8. Conclusion
This memo provides a generalized framework for solution
standards to meet the requirements. Further work should be
done to specify the interfaces between the user and NSP,
NAS and mAAA, mAAA and MACF and NSP-mAAA and CP-AAA
(presented in 5.2.)
Normative References
[1] Hayashi, et. al., "Requirements for Multicast AAA
coordinated between Content Provider(s) and Network
Service Provider(s)", draft-ietf-mboned-maccnt-req-
05.txt, September 2007, Work in Progress.
[2] RFC-3810, Vida, R. and L. Costa, "Multicast Listener
Discovery Version 2 (MLDv2) for IPv6", June 2004.
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[3] RFC-3376, Cain B., et.al., "Internet Group Management
Protocol, Version 3", October 2002.
[4] Ooghe, et. al, "Framework and Requirements for an
Access Node Control Mechanism in Broadband Multi-
Service Networks", draft-ietf-ancp-framework-05.txt,
February 2008, Work in Progress.
Authors' Addresses
Hiroaki Satou
NTT Network Service Systems Laboratories
3-9-11 Midoricho, Musashino-shi, Tokyo, 180-8585
Japan
Phone : +81 422 59 4683
Email : satou.hiroaki@lab.ntt.co.jp
Hiroshi Ohta
NTT Network Service Systems Laboratories
3-9-11 Midoricho, Musashino-shi, Tokyo, 180-8585
Japan
Phone : +81 422 59 3617
Email: ohta.hiroshi@lab.ntt.co.jp
Christian Jacquenet
France Telecom
3, avenue Francois Chateau
CS 36901, 35069 Rennes Cedex, France
Phone: +33 2 99 87 63 31
Email: christian.jacquenet@francetelecom.com
Tsunemasa Hayashi
NTT Network Innovation Laboratories
1-1 Hikari-no-oka, Yokosuka-shi, Kanagawa, 239-0847
Japan
Phone: +81 46 859 8790
Email: tsunemasa@gmail.com
Haixiang He
Nortel
600 Technology Park Drive
Billerica, MA 01801, USA
Phone: +1 978 288 7482
Email: haixiang@nortel.com
Comments
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Internet Draft AAA Framework for Multicasting Feb. 2008
Comments are solicited and should be addressed to the
mboned working group's mailing list at
mboned@lists.uoregon.edu_and/or the authors.
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Internet Draft AAA Framework for Multicasting Feb. 2008
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